6x + 3y - 7 + 2y in this formula
their are four terms 6x, 3y,7
and 2x
Annotations:
these terms are connected by + and - signs
terms such as 2x,x and 5x are called LIKE TERMS
Expanding Brackets
Annotations:
always keep the operation in the formula
Operation:
a word for these signs altogether +,-,x and division sign
E.G 6(x + 5) you would work this formula out
by multiplying the numbers outside of the
bracket with the letters or numbers inside
the brackets. the answer is : 6x + 30
Factorising
e.g. 10x +15 = 5 (2x + 3) -
step one : find the HCF - the
largest number/ letter that
will go into a term and put
it outside the bracket - step
two : work out what to
multiply this number by to
get each term
Substitution
e.g. p=3 r=7
answer - p+ r
= 3+7= 10
p* + r* answer - 3* +
7* the severn to the
power of two = 7x7 so
the sum becomes 9 +
49 = 58
Annotations:
the * stand for power of in this case power of 2
Deriving a Simple Formula
e.g. plumber £50 call out and £25 per hour to work this out you
would put this columns the first column is number of hours the
second column cost of hours which is the money per hour so
you would multiply the hour and cost per hour together then
your next column is the call out charge then finally the total cost
-
these examples of brackets tell us what we
do to both sides 1. x + 5 = 12 so we subtract 5
away from x so x is on its own but we have
to do the same to the other side so 12 - 5 = 7
so the answer is x = 7